Figure 1. Coordinated ciliary beating and arrests in Platynereis larvae.
(A–B,D) Scanning electron micrographs of 72 hr-post-fertilization larvae, (A) ventral view, (B) lateral view, (D) anterior view, close up. The structures dorsal to the crescent cell are non-motile sensory cilia. (C) Serial TEM reconstruction of ciliary band cells, lateral view. Nuclei of ciliary band cells are shown as spheres. The nervous system (brain and ventral nerve cord) is shown in light grey. (E) Kymographs of spontaneous ciliary activity from an immobilized 72 hr-post-fertilization larva. Arrowheads indicate the beginning of ciliary arrests. (F) Ventral view of the left half of a 72 hr-post-fertilization larva in a calcium-imaging experiment (left panel) with the corresponding differential interference contrast (DIC) image (right panel). (G) GCaMP6s signal from the prototroch and paratroch ciliary bands. A kymograph of ciliary activity in paratroch III is shown below. (H) GCaMP6s signal recorded from the prototroch of a 48 hr-post-fertilization larva at 45 frames per second. White areas in the kymograph correspond to periods of arrest. The boxed area is shown enlarged in the inset. Scale bars, 50 μm (A), 10 μm (D).